be compacted with the means available. Suggested ranges of workability of concrete measured in accordance with IS 1199 are given below:
7.1
The concrete mix proportions chosen should be such that the concrete is of adequate workability for the placing conditions of the concrete and can properly
| Placing Conditions | Degree of Workability | Slump (mm) |
|---|---|---|
| (1) | (2) | (3) |
| Blinding concrete; | Very low | See 7.1.1 |
| Shallow sections; | ||
| Pavements using pavers | ||
| Mass concrete; | Low | 25-75 |
| Lightly reinforced sections in slabs, beams, walls, columns; | ||
| Floors; | ||
| Hand placed pavements; | ||
| Canal lining; | ||
| Strip footings | ||
| Heavily reinforced sections in slabs. | Medium | 50-100 |
| beams, walls, columns; | ||
| Slipform work; | 75-100 | |
| Pumped concrete | ||
| Trench fill; | High | 100-150 |
| In-situ piling | ||
| Tremie concrete | Very high | See 7.1.2 |
NOTE-For most of the placing conditions, internal vibrators (needle vibrators) are suitable. The diameter of the needle shall be determined based on the density and spacing of reinforcement bars and thickness of sections. For tremie concrete, vibrators are not required to be used (see also 13.3).
7.1.1
In the 'very low' category of workability where strict control is necessary, for example pavement quality concrete, measurement of workability by determination of compacting factor will be more appropriate than slump (see IS 1199) and a value of compacting factor of 0.75 to 0.80 is suggested.
7.1.2
In the 'very high' category of workability, measurement of workability by determination of flow will be appropriate (see IS 9103).